11321: Misconfigured webhook

An incoming message reached one of your Twilio numbers, but Twilio could not send the webhook request because the configured URL is invalid. Configure the message URL in the Twilio Console or with the Messaging REST API, and make sure Twilio can reach the endpoint over the public internet.

• The phone number or Messaging Service is configured with a malformed webhook URL.

• Verify the URL in the Twilio Console to make sure it is correct and accessible.
• Use a fully qualified URL that includes the protocol, hostname, file path, and properly URL-encoded query parameters.
• Make sure the endpoint is reachable from the public internet.

• Twilio's request to your incoming message Webhook URL
• Webhooks security
• How to Configure a Twilio Phone Number to Receive and Respond to Messages